Slow Monster rebuild

[350TSS]

Spent last couple of days working on the rear tail light fitting, first day, progress was made which came to an abrupt end, the second day was very productive mainly because of the experience of the first day.
On the first day I cut out the shape of the fitting from the 3mm road sign and then tried to solder/weld the 2mm vertical element to it. It would not take properly and if I got it hot enough to take it moved so it had to be re-done. Also the clamps I was using were aluminium and were first acting as a heat sink and second when they got hot they expanded and no longer clamped the two parts together.
It was very frustrating. I think the road sign is dural rather than aluminium either that or the easyweld stuff does not like joining dissimilar thickness materials, because the heat transfer and cool down is different. I decided therefore to re-make the whole thing in 2mm sheet aluminium.
I was very aware that this is not a very vibration resistant or robust choice so my design concentrated on light weight (so that vibration would not be such an issue) and wherever possible maximizing the section to provide rigidity. All 4 mounting points would also have to be rubber mounted which means that the top hat sections I turned up to mount the under seat tray would have to be re-made to a different design. (good job I bought 2 metres of 25mm aluminium bar)
I also realized that the design I was contemplating on the first day would not work because the number plate hanger bracket was too far forward and would end up either touching the rear tyre on full suspension deflection or it would have to be angled so far out of the vertical as to be hopelessly illegal.
I had previously machined up some plugs to go in the truncated frame rails these were tapped 6mm to take a male/ female 25mm x 25mm vibration mount. There are also 2 projection welded 6mm nuts on the rear seat support which hold the seat latch. So I have 2 mounting points approximately horizontal and two approximately vertical.
The complexity is that the frame rails are not parallel but rather taper inwards and point slightly downwards and the seat latch bolts are not symmetrical around the centre-line of the bike. Added to that I have not yet made the seat itself and I want the light unit to fit flush to the bottom of the seat unit. Getting the slope of the light unit to fit to a non-existent seat was therefore a bit challenging.

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[Jez900ie]

Its brilliant reading your descriptions; the determination to resolve the issues without angst. Its also great to see the results. I'm definitely impressed.

[350TSS]

Jez900ie
Thanks - if you were in my garage two days ago you would not have thought there was a lack of angst. I spent ages cutting the 3 mm plate then it would not weld/solder and in the process I managed to burn the tip of my ring finger and left wrist. The air was blue for about half an hour, mainly because I realised that I would have to do it all again in 2mm.
Some more pictures of the rear light unit, incidentally the LED strip is wired to provide a) rear light, b) brake light and 50% on each side is an indicator. I will be using 2, one each side and will wire it so one half flashes hopefully in a sequential turn signal (remember 1965 Ford Thunderbird and some modern Audis have it).

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[350TSS]

Although the "welding" looks a bit ragged in the pictures I am confident that it has taken properly, wherever you tap the structure with a metallic object it "rings" hopefully implying integrity. The 3mm version never had anything other than a dull "thunk"

[350TSS]

Thought about the number plate bracket and made one from the 3mm road sign but felt that it would vibrate too much particularly at about 200 mm away from the mounting points.

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Decided I needed some section within the design to provide a bit more rigidity, thought about folding the edges but the attachment at the top need to fold rearward to allow a flat surface to bolt to the frame rail vibration mounts and the lower part needed to fold forwards to provide a flat surface for the number plate to attach to. Inevitably there would not /could not be a fold where the two surface met and this would be a weak spot.

I had some 8mm aluminium tube so I thought about how I would bend it (having annealed it first).
I knocked up a 9mm x 3 ply sandwich with the two outer layers describing the outline of what I wanted for the outside diameter of the tube and the inner sandwich filler being the inner diameter. This took some time and I had to wait overnight for the evo stik wood glue (really good strong stuff) to set. I found a longish spring with an 8mm bore and proceeded to try and bend the tube. With the spring in place the tube did not quite fit in my jig, also to bend tube effectively you have to go past the line you want and allow the metal to spring back. My jig was effectively scrap so I just bent it by hand with the spring around the tube. It came out not quite (but almost) square, given that there were 7 bends required in 3 planes I was quite chuffed.
I then made up some 3 x 2mm fillets to provide a mounting plate for the whole unit (1) and the number plate (2).

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I then proceeded to "weld" them together. Where the two ends of the tube butted together at the top I cut a strip of 2mm sheet into a thin strip and forced it into both ends of the tube , then pressed them together. I clamped the fillet strip in and clamped it together with some aluminium clamps and heated it up. With the clamps on in the past the heat needed is extensive before the filler material flows so I thought I would get it good and hot. With steel you can see how hot it is it goes from cherry red to orange to almost yellow. Aluminium just continues to look like aluminium. When I applied the filler rod about 1omm either side of the join just collapsed as the aluminium melted - I could have cried. The only consolation is that it will be right up under the seat hidden by the rear light, but I will always know it is there

[utopia]

Originally Posted by 350TSS

The only consolation is that it will be right up under the seat hidden by the rear light, but I will always know it is there

I remember hearing many years ago that Tibetan rugs always have an intentional imperfection in them ... otherwise they would be perfect, and only God can be that.

This thought often makes such minor errors easier to live with .. even though I'm not religious (in the conventional sense).

[Dirty]

Originally Posted by utopia

I remember hearing many years ago that Tibetan rugs always have an intentional imperfection in them ... otherwise they would be perfect, and only God can be that.

This thought often makes such minor errors easier to live with .. even though I'm not religious (in the conventional sense).

Its Persian rugs. Tibetans are Buddhist, don't have a 'god' per se and are much more relaxed about that sort of thing anyway

The idea of the 'deliberate flaw' can be found in many cultures and their objects. Denotes a special sort of arrogance in the artist IMO

[utopia]

Originally Posted by Dirty

Its Persian rugs. Tibetans are Buddhist, don't have a 'god' per se and are much more relaxed about that sort of thing anyway

The idea of the 'deliberate flaw' can be found in many cultures and their objects. Denotes a special sort of arrogance in the artist IMO

Yes, not Tibetans of course .. my daft mistake.
Not too sure about your "arrogance" comment though .. I see it more as humility myself.

For what its worth, my own view on perfection is that its like infinity .. it denotes a theoretical absolute maximum in time and space, which is both impossible to define and is in any case a subjective judgement according to the eye of the beholder.
Something to be constantly aimed for, but never achieved.
I guess that sounds more Buddist than anything .. possibly the reason for my misquote.
The good thing about all that is that it suggests that "near perfection" is the best outcome that it is possible to achieve, and that there are many, equally valid versions of this.
Which is why I can fully appreciate everyone else's custom monster creations while at the same time I can (and do) consider mine to be the best motorcycle in the world, ever.
Here endeth today's reading.

[Dirty]

Originally Posted by utopia

Yes, not Tibetans of course .. my daft mistake.
Not too sure about your "arrogance" comment though .. I see it more as humility myself.

I think it takes an arrogance to assume perfection in ones own art. Humility would assume imperfection and therefore negate the need to create one.

In any case an imperfection could perfect an object. For instance I doubt that antique Persian rug collectors would buy one that didn't have the flawed stitch, therefore making it 'perfect'.

[350TSS]

The above posts remind me of the rather prolonged discussion of the meaning of "quality" in Zen and the art of motorcycle maintenance, a book I do not remember finishing.
I started this re-build with the object of doing as much as I can myself and doing it as well as I can. Part of me is dissatisfied that the bracket is not quite square, maybe 3mm out on one of the bends, and I do want to do it again properly, that means making a new jig to a different design and bending and welding it all over again. This will take me a minimum of 6 hours. The botch of the weld on the joint in the tubes adds to that desire.
Against this is I am not getting any younger and I do want to ride this thing hopefully next spring (March 2018) and I have loads and loads to do and it is only a number plate bracket anyway and the flaws will be barely noticeable. However, if I start compromising now that is a slippery slope. On balance a Mk2 number plate bracket seems probable.

[Dirty]

Hi 5 Utopia, it worked

[utopia]

Ha .. I do remember finishing "Zen" but only after numerous restarts and even then I was left in some uncertainty.
Your road-sign 3mm ally is in the same vein as the beer-can handlebar clamp shims .. if you recall ?

I was going to refrain from adding further comment for fear of cluttering the thread, but.....
The rugmaker might be worried (though foolishly) about accidentally creating perfection while merely trying to do his humble best ....?
I could go on and talk of chaos and the dance of Shiva, but maybe that should be reserved for a discussion over a brew or two of some sort .,.. on me.
Suffice to say, there's nothing wrong with the odd flaw or scar as long as they are good, honest ones, in fact a case can be made to suggest that they are a vital ingredient.
Oh, and I have no time for the rug collector who would prize something merely because it is rare or unusual .. He has no sense of quality and is merely interested in abstract market value.
He would probably have no interest in my old 750 whatsoever (even though it "is" the best motorcycle in the world, ever).

[350TSS]

Been a bit quiet recently - 3 reasons - 1. PC finally died: 2. Lathe broke another drive belt and I had to dismantle it to find the cause and 3. I had what I would call an "unguarded moment".
I manufactured a jig from some old shelving angle in the hope I could re-make the number plate hanger bracket accurately.

[350TSS]

Sorry about duplication - meant to post this one

[350TSS]

Whilst making the jig I used up all my 115mm cutting discs so I thought I could use a much used one from my 225mm angle grinder unfortunately the smallest one in the drawer was 125mm which would not fit within the guard. Undeterred I removed the guard and carried on cutting - you can guess the rest.